Recently, resolution of an imaging device equipped in a mobile device has increased. Also, according to decrease in a pixel size of an image sensor, high performance and high transmittance of the imaging device are being required.
However, to implement the high performance and high transmittance in a conventional imaging device, height of a space for receiving a lens needs to be increased for an entire length of the imaging device. In this case, a clearance space behind the lens is reduced while an aperture of an entrance pupil to which light is incident is increased. As a result, it becomes difficult to manufacture a small size product appropriate for the mobile device.